Caption: Acupuncture model. Front view of a model of the human head marked with acupuncture points (labelled dots) and meridians (coloured lines). Also seen is the musculature that lies under the skin (left). Acupuncture is a traditional Chinese system of medicine. It supposes that the meridians act as channels for flowing life force or chi. Each of the meridians is believed to connect through internal pathways to one of the internal organs. Diseases are considered to be due to interruptions in the flow of chi. Inserting needles into the correct points is thought to restore the flow and cure disease.